New 'hover' train uses conductive coating

Currently undergoing trial runs in China, the Transrapid Consortium's new 'Maglev' super-train, which hovers above tracks on an electromagnetic field, relies on conductive coatings on the track power cables to achieve maximum efficiency and aid passenger comfort

. Typically used on temperature-sensitive substrates and automotive extrusions, the Xylan1642 flexible coating, developed by Runcorn-based Whitford Plastics, is critical to the successful running of the train and is both weather-resistant and chemical-resistant. The coating, which also has a very low coefficient of friction, drains away static and disperses it elsewhere, so it cannot interfere with the smooth running of the train. At speeds of more than 400km/h, static build-up can cause the train to sway, causing travel sickness in passengers. The coatings can be applied by conventional spray methods and operate in temperatures of –30 deg C to 100 deg C and come in a variety of colours. The propulsion system for Maglev trains uses the principle of electromagnetic attraction and repulsion. A magnetic field created by electrified coils in the guideway walls and track repels guidance magnets attached to the train's underside, suspending the train 1cm above the track on the opposing magnetic forces. The propulsion coils located in the sidewalls of the track use an alternating current, which creates a shifting magnetic field. On-board superconducting magnets are attracted and pushed by this shifting field, propelling the Maglev train along. The first Maglev train is due to go into service early next year on the 70km connection between Pudong Shanghai International Airport and Shanghai's financial district. DP Pointers * Track power cables for the new Maglev super trains are coated with a two-stage conductive surface coating, Xylan 1642, which has a very low coefficient of friction and is both weather- and chemical-resistant * The coating helps drain away and disperse static, which can cause the train to sway * The coatings can withstand temperatures of between –30 deg C and 100 deg C